Since we launched v2.1.0 of the site we've also started to collect data to try and surface "trending threads" on the site. We're now happy to release this to the public in the form of a trending threads list on the main forums page, a sitewide trending threads page, and the ability to sort forums by trending threads (eg here for Loungin' trending).

Here's some background on this:

trending threads are threads that are seeing strong activity in a short period of time and becoming more active than they were in the past.

sitewide trending threads seem to reveal the most interesting patterns, while a single forum's trending threads will look a lot like the "recently replied" threads in that forum.

shares and subscriptions to threads have a pretty strong influence on trending. If a thread is shared by more people onto their walls it will trend higher. This gives users a chance to direct the community as to what threads are worth checking out, which is what shares are intended to allow.

it's possible to show trending threads within an entire community or a category.

How threads trend

Several signals determine whether a thread is trending. In general the system tries to find threads that may be of interest to many people NOW more so than before. It also looks for things like shares and thread subscriptions. This makes sense because if you and others are sharing your threads it means the thread is of interest and we take that as a signal to trend it higher.

Trending Tweaks

Trying to find trending threads is very difficult for the system, so don't expect this to be a perfect representation of what is "popular" and "hot" on the site. However, after looking at this for weeks I think we have a reasonable ability to detect interesting topics and we will continue to tweak this to make it more fun and useful over time.